The present invention pertains to a method for estimating a sound source position in a space with high accuracy using a microphone installed on a robot moving in the space.
In recent years, service robots existing with people in a space and moving for providing various kinds of services have been developed. A microphone is installed in such a robot as communication means with people and some robots have a function to have conversations with people using the voice recognition technology. Also developed is a security robot which patrols a building, detects abnormality by a camera or microphone installed thereon and reports it immediately. Further, proposed is a multipurpose and efficiently utilized robot equipped with both of a service function and a security function for providing services in the day time and security at night.
A robot with a security function is required to detect types of abnormality the same as or more than a security guard of person. As a corollary to it, the robot is expected to detect unusual sounds while guarding. Two types of function are required for detecting sound abnormalities, one is a function to determine whether an observed sound is abnormal, and the other is a function to send the type of the sound, the occurrence time of the sound and the position of the sound.
As a technique to send the position of sound, a technique is developed to locate the position of a sound source from a sound waveform observed by a mobile robot equipped with a microphone.    Patent Literature 1 discloses a method for measuring a sound source position accurately by the principal of triangulation.    Patent Literature 1: JP2011-149782A